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1.
J Contam Hydrol ; 263: 104339, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38564944

RESUMEN

Plastic particles, measuring <5 mm in size, mainly originate from larger plastic debris undergoing degradation, fragmenting into even smaller fragments. The goal was to analyze the spatial diversity and polymer composition of microplastics (MPs) in North Chennai, South India, aiming to evaluate their prevalence and features like composition, dimensions, color, and shape. In 60 sediment samples, a combined count of 1589 particles were detected, averaging 26 particles per 5 g-1 of dry sediment. The water samples from the North Chennai vicinity encompassed a sum of 1588 particles across 71 samples, with an average of 22 items/L. The majority of MPs ranged in size from 1 mm to 500 µm. The ATR-FTIR results identified the predominant types of MPs as polystyrene, polyvinyl chloride, polyethylene, polyethylene terephthalate, and polypropylene in sediment and water. The spatial variation analysis revealed high MPs concentration in landfill sites, areas with dense populations, and popular tourist destinations. The pollution load index in water demonstrated that MPs had contaminated all stations. Upon evaluating the polymeric and pollution risks, it was evident that they ranged from 5.13 to 430.15 and 2.83 to 15,963.2, which is relatively low to exceedingly high levels. As the quantity of MPs and hazardous polymers increased, the level of pollution and corresponding risks also escalated significantly. The existence of MPs in lake water, as opposed to open well water, could potentially pose a cancer risk for both children and adults who consume it. Detecting MPs in water samples highlights the significance of implementing precautionary actions to alleviate the potential health hazards they create.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos , Microplásticos , Contaminantes Químicos del Agua , Microplásticos/análisis , India , Contaminantes Químicos del Agua/análisis , Sedimentos Geológicos/química , Sedimentos Geológicos/análisis , Humanos , Medición de Riesgo , Plásticos/análisis
2.
Environ Res ; 251(Pt 1): 118631, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38452914

RESUMEN

Plastic waste has become a global issue and a threat to the ecosystem. The present study isolated polyurethane (PU) degrading bacterial species from soil dumped with plastic wastes. Four bacterial isolates, RS1, RS6, RS9 and RS13 were obtained and their ability to degrade PU in a synthetic medium with PU as a sole source of carbon was assessed individually. After thirty days of incubation, the highest PU weight loss of 67.36 ± 0.32% was recorded in the medium containing RS13 isolate. The results of FTIR revealed the occurrence of carbonyl peaks. The putative isolate RS13 confirmed with the genus Moraxella according to 16S rRNA gene sequencing and the isolate was specified as Moraxella catarrhalis strain BMPPS3. The restriction analysis of Moraxella catarrhalis strain BMPPS3 revealed that the GCAT content to 51% and 49% correspondingly. Moraxella catarrhalis strain BMPPS3 was able to colonize on PU surface and form a biofilm as revealed by SEM investigation. Fatty acids and alkanes were found to be the degradation products by GC-MS analysis. The presence of these metabolites facilitated the growth of strain RS13 and suggested that ester hydrolysis products had been mineralized into CO2 and H2O. Extracellular biosurfactant synthesis has also been found in Moraxella catarrhalis strain BMPPS13 inoculated with synthetic media and mineral salt media containing PU and glucose as carbon sources, respectively with a significant level of cell-surface hydrophobicity (32%). The production and activity of extracellular esterase showed consistent increase from day 1-15 which peaked (1.029 mM/min/mg) on day 24 significantly at P < 0.001. Crude biosurfactants were lipopeptide-based, according to the characteristic investigation. According to this study findings, Moraxella catarrhalis produces biosurfactants of the esterase, urethanase and lipase (lipopeptide) types when carbon source PU is present.


Asunto(s)
Biodegradación Ambiental , Moraxella catarrhalis , Poliuretanos , Moraxella catarrhalis/genética , Moraxella catarrhalis/metabolismo , Moraxella catarrhalis/enzimología , Microbiología del Suelo , ARN Ribosómico 16S/genética , Biopelículas/crecimiento & desarrollo
3.
Environ Geochem Health ; 46(2): 67, 2024 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-38341826

RESUMEN

The jarosite waste used during this study consists of minute amount of arsenic that has a potential to be leached into environment when kept in open area. This study tried to recover arsenic from jarosite waste using hydrometallurgical treatment. The comprehensive characterization of jarosite samples was performed using various analytical techniques, including X-ray diffraction (XRD), Fourier transform Infrared (FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX), and it was characterized as natrojarosite. For optimal removal of arsenic, the response surface methodology (RSM) was applied with the key factors, including dosage (A), time (B), temperature (C), and acid concentration (D) on the recovery of arsenic. The results indicated that the dosage (A) and acid concentration (D) demonstrated significant positive effects on arsenic recovery. As expected, the higher dosage and acid concentration was associated with increased recovery percentages for the arsenic from jarosite. Whereas time (B) and temperature (C) did not exhibit statistically significant recovery of arsenic within the specified experimental range. The contour plots showed the optimal operating conditions for the highest recovery percentage was approximately 52.61% when 2.5 g of jarosite was treated with 10 mol/L acid for 150 min at operating temperature of 80°. Although our study showed very moderate recovery of arsenic, it is first report where arsenic has been removed from jarosite waste. Readjustment of range of operating parameters would provide more insight into the further optimization of the yield.


Asunto(s)
Arsénico , Arsénico/química , Compuestos Férricos/química , Sulfatos/química , Temperatura , Adsorción
4.
ACS Omega ; 8(37): 33229-33241, 2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37744785

RESUMEN

Herein, the impact of surface charge tailored of gold nanorods (GNRs) on breast cancer cells (MCF-7 and MDA-MB-231) upon conjugation with triphenylphosphonium (TPP) for improved photodynamic therapy (PDT) targeting mitochondria was studied. The salient features of the study are as follows: (i) positive (CTAB@GNRs) and negative (PSS-CTAB@GNRs) surface-charged gold nanorods were developed and characterized; (ii) the mitochondrial targeting efficiency of gold nanorods was improved by conjugating TPP molecules; (iii) the conjugated nanoprobes (TPP-CTAB@GNRs and TPP-PSS-CTAB@GNRs) were evaluated for PDT in the presence of photosensitizer (PS), 5-aminolevulinic acid (5-ALA) in breast cancer cells; (iv) both nanoprobes (TPP-CTAB@GNRs and TPP-PSS-CTAB@GNRs) induce apoptosis, damage DNA, generate reactive oxygen species, and decrease mitochondrial membrane potential upon 5-ALA-based PDT; and (v) 5-ALA-PDT of two nanoprobes (TPP-CTAB@GNRs and TPP-PSS-CTAB@GNRs) impact cell signaling (PI3K/AKT) pathway by upregulating proapoptotic genes and proteins. Based on the results, we confirm that the positively charged (rapid) nanoprobes are more advantageous than their negatively (slow) charged nanoprobes. However, depending on the kind and degree of cancer, both nanoprobes can serve as efficient agents for delivering anticancer therapy.

5.
Environ Toxicol Pharmacol ; 101: 104201, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37391053

RESUMEN

This study investigated the deltamethrin (DMN) induced harmful effects on Pangasius hypophthalmus using enzymatic activity, haematological, and histopathological changes. LC50 value was 0.021 mg/L at 96 h, and sublethal toxicity was tested for 45 days at two `concentrations (i.e., 1/5th and 1/10th of LC50). Haematological parameters and enzymatic activities significantly changed between DMN-exposed and control groups (p < 0.05). Histopathologically, both DMN doses induced liver hyperemia, hepatic cell rupture, necrosis, hypertrepheoid bile duct, shifting nuclei, vascular haemorrhage, and hepatocyte degeneration, while in gill, secondary lamellae destruction, a fusion of adjacent gill lamellae, hypertrophy, hyperplasia, adhesion, and fusion were noticed. Kidney developed melanomacrophages, increased periglomerular and peritubular space, vacuolation, decreased glomerulus, hyaline droplets in tubular cells, loss of tubular epithelium, distal convoluted segment hypertrophy, and granular layer in brain pyramid and Purkinje cell nucleus. But, limiting pesticide impacts on freshwater fish and their habitat requires a holistic, cradle-to-grave approach and toxicological studies.


Asunto(s)
Bagres , Insecticidas , Tiburones , Contaminantes Químicos del Agua , Animales , Insecticidas/metabolismo , Hígado , Hipotálamo , Agua Dulce , Branquias , Contaminantes Químicos del Agua/metabolismo
6.
Sci Total Environ ; 887: 163984, 2023 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-37164098

RESUMEN

The widespread use of Personal protective equipments (PPEs) by the healthcare professionals and public due to Corona Virus Disease (COVID-19) pandemic has become a new source for MFs pollution. Mismanaged plastic wastes and random dispose of used surgical face mask end up in large aquatic bodies via small waterways and waste water treatment plants (WWTPs). Microplastics/Microfibres (MPs/MFs) have recently been reported in a variety of aquatic and terrestrial ecosystems, including water, deep sea sediments, air and soil. Natural components like UV radiation and temperature play a major role in weathering of surgical masks. High loads of MPs/MFs emitted into the aquatic environment are easily consumed by organism's habitat in such ecosystem by disrupting the food chain and causing chronic health problems in the organisms including humans. The aim of this review article is to shed light on these issues and compile the most recent information available regarding the deterioration of surgical face masks in the environment as well as other contaminants and their presence in various environments, particularly with regard to methods that make use of exposure models, biomarkers of exposure, and their limitations. Along with this, the study focuses on identifying gaps in current understanding and highlighting prospective research directions. The literature on surgical face mask pollution and its effects on the biological and physiological systems of various organisms and ecosystems is critically analysed in this review. It also raises awareness of how to properly dispose of used surgical face masks and other PPEs.


Asunto(s)
COVID-19 , Contaminantes Químicos del Agua , Humanos , Plásticos , Ecosistema , Estudios Prospectivos , Contaminantes Químicos del Agua/análisis , Microplásticos , Biota
7.
Sci Total Environ ; 884: 163729, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37120020

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are highly carcinogenic substances and accumulate in water bodies through various industries. Due to their harmful effects on humans, it is very important to monitor PAHs in various water resources. In the present work, we report an electrochemical sensor based on silver nanoparticles synthesized using mushroom-derived carbon dots for the simultaneous determination of anthracene and naphthalene, for the first time. Pleurotus species mushroom was used to synthesize the carbon dots (C-dots) via the hydrothermal method and these C-dots were used as a reducing agent for the synthesis of silver nanoparticles (AgNPs). The synthesized AgNPs have been characterized through UV-Visible and FTIR spectroscopy, DLS, XRD, XPS, FE-SEM, and HR-TEM. Well-characterized AgNPs were used to modify glassy carbon electrodes (GCEs) by the drop-casting method. Ag-NPs/GCE has shown strong electrochemical activity towards the oxidation of anthracene and naphthalene at well-separated potentials in phosphate buffer saline (PBS) at pH 7.0. The sensor exhibited a wide linear working range of 250 nM to 1.15 mM for anthracene and 500 nM to 842 µM for naphthalene with the corresponding lowest detection limits (LODs) of 112 nM and 383 nM respectively with extraordinary anti-interference ability against many possible interferents. The fabricated sensor showed high stability and reproducibility. The usefulness of the sensor for the monitoring of anthracene and naphthalene in a seashore soil sample has been demonstrated by the standard addition method. The sensor gave better results with a high recovery percentage indicating the first-ever device to detect two PAHs at the single electrode with the best analytical results.


Asunto(s)
Agaricales , Contaminantes Ambientales , Nanopartículas del Metal , Humanos , Carbono/química , Nanopartículas del Metal/química , Plata/química , Reproducibilidad de los Resultados , Antracenos , Naftalenos
8.
Environ Res ; 228: 115900, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37059325

RESUMEN

Recent years have seen a lot of interest in transition metal carbides/carbonitrides (MXenes), Which is one of newly proliferating two-dimensional (2D) materials.The advantages and applications of synthesizing MXenes-based biosensing systems are interesting. There is an urgent requirement for synthesis of MXenes. Through foliation, physical adsorption, and interface modification,it has been proposed that many biological disorders are related to genetic mutation. Majority of mutations were discovered to be nucleotide mismatches. Consequently, accurate -nucleotide mismatched discrimination is crucial for both diagnosing and treating diseases. To differentiate between such a sensitivealterations in the DNA duplex, several detection methods, particularly Electrochemical-luminescence (ECL) ones, have really been investigated.Mn+1XnTx is common name for MXenes, a novel family of two-dimensional (2D) transition metal carbides, nitrides, and carbonitrides, where T stands for interface termination units (i.e. = O, OH, and/or F). These electronic characteristics of MXenes may be changed between conductive to semiconducting due to abundant organometallic chemistry.Solid-state ECL sensors predicated on MXene would provide the facile nucleotide detection and convenience for usage with minimal training, mobility and possibly minimal cost.This study emphasizes upcoming requirements and possibilities in this area while describing the accomplishments achieved in the usage and employing of MXenes in the research and development of facile biomarkerdetection and their significance in designing electrochemical sensors. Opportunities are addressed for creating 2D MXene materials sensors and devices with incorporated biomolecule sensing. MXenes Carry out this process sensors, address the advantages of using MXenes and their variants as detecting materials for gathering different types of data, and attempt to clarify the design principles and operation of related MXene-based sensors, such as nucleotide detection, Single nucleotide detectors, Cancer theranostics, Biosensing capabilities, Gliotoxin detection, SARS-COV-2 nucleocapsid detection, electrochemical sensors, visual sensors, and humidity sensors. Finally, we examine the major issues and prospects for MXene-based materials used in various sensing applications.


Asunto(s)
COVID-19 , Humanos , Biomarcadores , Nucleótidos , SARS-CoV-2
9.
Sci Rep ; 13(1): 2230, 2023 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-36754981

RESUMEN

Although gold nanoparticles based photodynamic therapy (PDT) were reported to improve efficacy and specificity, the impact of surface charge in targeting cancer is still a challenge. Herein, we report gold nanotriangles (AuNTs) tuned with anionic and cationic surface charge conjugating triphenylphosphonium (TPP) targeting breast cancer cells with 5-aminoleuvinic acid (5-ALA) based PDT, in vitro. Optimized surface charge of AuNTs with and without TPP kill breast cancer cells. By combining, 5-ALA and PDT, the surface charge augmented AuNTs deliver improved cellular toxicity as revealed by MTT, fluorescent probes and flow cytometry. Further, the 5-ALA and PDT treatment in the presence of AuNTs impairs cell survival Pi3K/AKT signaling pathway causing mitochondrial dependent apoptosis. The cumulative findings demonstrate that, cationic AuNTs with TPP excel selective targeting of breast cancer cells in the presence of 5-ALA and PDT.


Asunto(s)
Neoplasias de la Mama , Nanopartículas del Metal , Fotoquimioterapia , Humanos , Femenino , Proteínas Proto-Oncogénicas c-akt , Oro/farmacología , Fosfatidilinositol 3-Quinasas , Neoplasias de la Mama/tratamiento farmacológico , Nanopartículas del Metal/uso terapéutico , Ácido Aminolevulínico/farmacología , Apoptosis , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Línea Celular Tumoral
10.
J Appl Microbiol ; 134(2)2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36724285

RESUMEN

Environmental contamination brought on by the discharge of wastewater from textile industries is a growing concern on a global scale. Textile industries produce a huge quantity of effluents containing a myriad of chemicals, mostly dyes. The discharge of such effluents into the aquatic environment results in pollution that adversely affects aquatic organisms. Synthetic dyes are complex aromatic chemical structures with carcinogenic and mutagenic properties in addition to high biological oxygen demand (BOD) and chemical oxygen demand (COD). This complex aromatic structure resists degradation by conventional techniques. The bioremediation approach is the biological clean-up of toxic contaminants from industrial effluents. Biological treatment methods produce less or no sludge and are cost-effective, efficient, and eco-friendly. Microorganisms, mostly microalgae and bacteria, and, in some instances, fungi, yeast, and enzymes decolorize textile dye compounds into simple, non-toxic chemical compounds. Following a thorough review of the literature, we are persuaded that microalgae and bacteria might be one of the potential decolorizing agents substituting for most other biological organisms in wastewater treatment. This article presents extensive literature information on textile dyes, their classification, the toxicity of dyes, and the bioremediation of toxic textile industry effluent utilizing microalgae and bacteria. Additionally, it combines data on factors influencing textile dye bioremediation, and a few suggestions for future research are proposed.


Asunto(s)
Residuos Industriales , Industria Textil , Humanos , Biodegradación Ambiental , Residuos Industriales/análisis , Colorantes/metabolismo , Textiles
11.
Environ Pollut ; 320: 121009, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36634860

RESUMEN

Reclaimed water is highly required for environmental sustainability and to meet sustainable development goals (SDGs). Chemical processes are frequently associated with highly hazardous and toxic by-products, like nitrosamines, trihalomethanes, haloaldehydes, haloketones, and haloacetic acids. In this context, we aim to summarize the formation of various commonly produced disinfection by-products (DBPs) during wastewater treatment and their treatment approaches. Owing to DBPs formation, we discussed permissible limits, concentrations in various water systems reported globally, and their consequences on humans. While most reviews focus on DBPs detection methods, this review discusses factors affecting DBPs formation and critically reviews various remediation approaches, such as adsorption, reverse osmosis, nano/micro-filtration, UV treatment, ozonation, and advanced oxidation process. However, research in the detection of hazardous DBPs and their removal is quite at an early and initial stage, and therefore, numerous advancements are required prior to scale-up at commercial level. DBPs abatement in wastewater treatment approach should be considered. This review provides the baseline for optimizing DBPs formation and advancements in the remediation process, efficiently reducing their production and providing safe, clean drinking water. Future studies should focus on a more efficient and rigorous understanding of DBPs properties and degradation of hazardous pollutants using low-cost techniques in wastewater treatment.


Asunto(s)
Desinfectantes , Agua Potable , Nitrosaminas , Contaminantes Químicos del Agua , Purificación del Agua , Humanos , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Desinfección/métodos , Halogenación , Trihalometanos , Desinfectantes/química
12.
Sci Total Environ ; 858(Pt 1): 159681, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36302412

RESUMEN

Microplastics have been identified as an emerging pollutant due to their irrefutable prevalence in air, soil, and particularly, the aquatic ecosystem. Wastewater treatment plants (WWTPs) are seen as the last line of defense which creates a barrier between microplastics and the environment. These microplastics are discharged in large quantities into aquatic bodies due to their insufficient containment during water treatment. As a result, WWTPs are regarded as point sources of microplastics release into the environment. Assessing the prevalence and behavior of microplastics in WWTPs is therefore critical for their control. The removal efficiency of microplastics was 65 %, 0.2-14 %, and 0.2-2 % after the successful primary, secondary and tertiary treatment phases in WWTPs. In this review, other than conventional treatment methods, advanced treatment methods have also been discussed. For the removal of microplastics in the size range 20-190 µm, advanced treatment methods like membrane bioreactors, rapid sand filtration, electrocoagulation and photocatalytic degradation was found to be effective and these methods helps in increasing the removal efficiency to >99 %. Bioremediation based approaches has found that sea grasses, lugworm and blue mussels has the ability to mitigate microplastics by acting as a natural trap to the microplastics pollutants and could act as candidate species for possible incorporation in WWTPs. Also, there is a need for controlling the use and unchecked release of microplastics into the environment through laws and regulations.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Purificación del Agua , Microplásticos , Plásticos , Aguas Residuales/análisis , Eliminación de Residuos Líquidos , Ecosistema , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente
13.
Chemosphere ; 313: 137475, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36528154

RESUMEN

Anthropogenic toxins are discharged into the environment and distributed through a variety of environmental matrices. Trace contaminant detection and analysis has advanced dramatically in recent decades, necessitating further specialized technique development. These pollutants can be mobile and persistent in small amounts in the environment, and ecological receptors will interact with it. Despite the fact that few researches have been undertaken on invertebrate exposure, accumulation, and biological implications, it is apparent that a wide range of pollutants can accumulate in the tissues of aquatic insects, earthworms, amphipod crustaceans, and mollusks. Due to long-term stability during long-distance transit, a number of chemical and microbiological agents that were not previously deemed pollutants have been found in various environmental compartments. The uptake of such pollutants by the aquatic organism is done through the process of bioaccumulation when dangerous compounds accumulate in living beings while biomagnification is the process of a pollutant becoming more hazardous as it moves up the trophic chain. Organic and metal pollution harms animals of every species studied so far, from bacteria to phyla in between. The environmental protection agency says these poisons harm humans as well as a variety of aquatic organisms when the water quality is sacrificed in typical wastewater treatment systems. Contrary to popular belief, treated effluents discharged into aquatic bodies contain considerable levels of Anthropogenic contaminants. This evolution necessitates a more robust and recent advancement in the field of remediation and their techniques to completely discharge the various organic and inorganic contaminants.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Animales , Humanos , Ecosistema , Contaminantes Ambientales/análisis , Contaminantes Químicos del Agua/análisis , Organismos Acuáticos , Calidad del Agua , Monitoreo del Ambiente/métodos
14.
Environ Res ; 216(Pt 1): 114498, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36209791

RESUMEN

The fungal symbiosis with the plant root system is importantly recognized as a plant growth promoting fungi (PGPFs), as well as elicitor of plant defence against different biotic and abiotic stress conditions. Thus PGPFs are playing as a key trouper in enhancing agricultural quality and increased crop production and paving a way towards a sustainable agriculture. Due to increased demand of food production, the over and unscientific usage of chemical fertilizers has led to the contamination of soil by organic and inorganic wastes impacting on soil quality, crops quality effecting on export business of agricultural products. The application of microbial based consortium like plant growth promoting fungi is gaining worldwide importance due to their multidimensional activity. These activities are through plant growth promotion, induction of systemic resistance, disease combating and detoxification of organic and inorganic toxic chemicals, a heavy metal tolerance ability. The master key behind these properties exhibited by PGPFs are attributed towards various secretory biomolecules (secondary metabolites or enzymes or metabolites) secreted by the fungi during interaction mechanism. The present review is focused on the multidimensional role PGPFs as elicitors of Induced systemic resistance against phytopathogens as well as heavy metal detoxifier through seed biopriming and biofortification methods. The in-sights on PGPFs and their probable mechanistic nature contributing towards plants to withstand heavy metal stress and stress alleviation by activating of various stress regulatory pathways leading to secretion of low molecular weight compounds like organic compounds, glomalin, hydrophobins, etc,. Thus projecting the importance of PGPFs and further requirement of research in developing PGPFs based molecules and combining with trending Nano technological approaches for enhanced heavy metal stress alleviations in plant and soil as well as establishing a sustainable agriculture.


Asunto(s)
Metales Pesados , Suelo , Biodegradación Ambiental , Secretoma , Metales Pesados/toxicidad , Productos Agrícolas/metabolismo , Semillas/metabolismo , Hongos
15.
Sci Total Environ ; 859(Pt 2): 160260, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36400296

RESUMEN

Among various natural biowastes availability in the environment, agricultural residues showed great impacts. It is due to huge availability and cheap carbon source, creating big challenges for their utility and systematic reduction. Objective of this review is to address the waste biomass availability and huge quantities issues and also put effort to minimize this nutrient load via biotransforming into value-added products. Different wastes (organic/inorganic) generation with their negative issues are due to numbers of developmental and social activities, reported. Currently, various efforts are found for these wastes minimization via generation of different types of value-added products (biogas, bioH2, alcoholic fuel, organic acids and others products) and these wastes in municipal cities are also reported with production of advanced biofuels as promising outcomes. For hydrolysis of complex organic resources including lignocellulosic biomasses, physicochemical, structural or compositional changes are needed that aid in conversion into sugar and organic compounds such as biofuels. So, efficient and effective pretreatment processes selection (physical, biological, chemical or combined one) is critical to achieve these hydrolysis goals and resultant cellulose or hemicellulose components can be accessible by biological catalysis. These can achieve final hydrolysis and fermentative or monomer sugars. And later, synthesis of fuels or value-added products during microbial fermentation or biotransformation processes can be achieved. This review discusses pretreatment techniques for improved hydrolysis for fermentative sugar with emphasis on reduced quantities of toxic compounds (furfural compound) in hydrolyzed biomasses. Minimum deterioration fuel economy also reported with production of different bioproducts including biofuels. Additionally, impacts of toxic products and gasses emission are also discussed with their minimization.


Asunto(s)
Contaminación del Aire , Biocombustibles , Biomasa , Hidrólisis , Fermentación , Carbohidratos , Azúcares , Lignina/metabolismo
16.
Environ Monit Assess ; 195(1): 75, 2022 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-36334179

RESUMEN

Quorum sensing (QS) is a system of bacteria in which cells communicate with each other; it is linked to cell density in the microbiome. The high-density colony population can provide enough small molecular signals to enable a range of cellular activities, gene expression, pathogenicity, and antibiotic resistance that cause damage to the hosts. QS is the basis of chronic illnesses in human due to microbial sporulation, expression of virulence factors, biofilm formation, secretion of enzymes, or production of membrane vesicles. The transfer of antimicrobial resistance gene (ARG) among antibiotic resistance bacteria is a major public health concern. QS-mediated biofilm is a hub for ARG horizontal gene transfer. To develop innovative approach to prevent microbial pathogenesis, it is essential to understand the role of QS especially in response to environmental stressors such as exposure to antibiotics. This review provides the latest knowledge on the relationship of QS and pathogenicity and explore the novel approach to control QS via quorum quenching (QQ) using QS inhibitors (QSIs) and QQ enzymes. The state-of-the art knowledge on the role of QS and the potential of using QQ will help to overcome the threats of rapidly emerging bacterial pathogenesis.


Asunto(s)
Antiinfecciosos , Percepción de Quorum , Humanos , Percepción de Quorum/fisiología , Virulencia , Monitoreo del Ambiente , Bacterias , Biopelículas , Antibacterianos/toxicidad , Antibacterianos/metabolismo , Antiinfecciosos/metabolismo
17.
Bioresour Technol ; 364: 128057, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36195218

RESUMEN

Reducing CO2 emissions using biomass is gaining popularity as an environmentally friendly strategy. Due to high growth rates, low production costs, and ability to withstand harsh conditions, microalgae have become quite popular. Microalgae may also undertake photosynthesis, converting CO2 and solar energy into sugar before becoming biomass, making them an excellent source of renewable and promising biofuels. CO2 sequestration and biofixation was utilized to compare the synthesis of biodiesel as a third-generation biofuel from various types of wastewater was also used as a source for the algal cultivation. This review article focuses on recent developments, research discoveries in the field of microalgal CO2 capture modification and the optimization of conversion efficiency. This review is intended to serve as a helpful and reference for the use of wastewater treatment with microalgae to collect CO2. The overarching objective of this study is to assist wastewater treatment systems in achieving carbon neutrality.


Asunto(s)
Microalgas , Aguas Residuales , Carbono , Dióxido de Carbono , Biocombustibles , Biomasa
18.
Chemosphere ; 308(Pt 1): 136165, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36037954

RESUMEN

Heavy-metal-bearing wastewater is among the most formidable challenges the mining industry currently faces in maintaining its social license to operate. Amongst the technologies available for metal ion adsorption, bioinspired engineering nanomaterials have emerged as one which exhibits great promise. However, current processes used for the preparation of adsorbents (including nanoscale activated carbon and biochar) represent a source of adverse impacts on the environment. In contrast, the application of biogenic-nanoparticles, i.e., those derived from processes catalysed by microbiota, has received significant attention in the last few years. Coupled with this, the use of naturally occurring reagents is of major importance for the sustainability of this emerging industry. This paper analyses the life cycle assessment (LCA) of the synthesis of adsorbents derived from agricultural wastes. Moreover, rather than simply recovering the ecotoxic metals from wastewater, the potential to valorise dissolved metals into high-value metallic nanoparticle products is discussed. LCA analysis revealed that the adsorbent had some adverse impact on the environment. The agricultural wastes contributed 27.86% to global warming, 54.64% to ozone formation, 33.06% to fine particles, and 98.24% to marine eutrophication. Mining wastewater is an important, and largely currently unexploited, source of metal value. However, the often-low concentration of such metals dictates that their conversion into high-value products (such as engineered nanoparticles) is an important new research frontier. Within this the use of biosynthesis methods has emerged as having great potential due to a range of beneficial attributes, including low cost, high efficacy and/or environmental compatibility.


Asunto(s)
Nanopartículas del Metal , Metales Pesados , Ozono , Contaminantes Químicos del Agua , Adsorción , Carbón Orgánico , Iones , Aguas Residuales
19.
Environ Res ; 214(Pt 3): 114018, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35961544

RESUMEN

Every year, 180 billion tonnes of cellulose are produced by plants as waste biomass after the cultivation of the desired product. One of the smart and effective ways to utilize this biomass rather than burn it is to utilize the biomass to adequately meet the energy needs with the help of microbial cellulase that can catalytically convert the cellulose into simple sugar units. Marine actinobacteria is one of the plentiful gram-positive bacteria known for its industrial application as it can produce multienzyme cellulase with high thermal tolerance, pH stability and high resistant towards metal ions and salt concentration, along with other antimicrobial properties. Highly stable cellulase obtained from marine actinobacteria will convert the cellulose biomass into glucose, which is the precursor for biofuel production. This review will provide a comprehensive outlook of various strategic applications of cellulase from marine actinobacteria which can facilitate the breakdown of lignocellulosic biomass to bioenergy with respect to its characteristics based on the location/environment that the organism was collected and its screening strategies followed by adopted methodologies to mine the novel cellulase genome and enhance the production, thereby increasing the activity of cellulase continued by effective immobilization on novel substrates for the multiple usage of cellulase along with the industrial applications.


Asunto(s)
Actinobacteria , Celulasa , Actinobacteria/genética , Actinobacteria/metabolismo , Bacterias/metabolismo , Biocombustibles , Biomasa , Celulasa/química , Celulasa/genética , Celulasa/metabolismo , Celulosa/metabolismo
20.
Chemosphere ; 306: 135520, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35780979

RESUMEN

Graphene is a high surface area special carbon compound with exceptional biological, electronic and mechanical properties. Graphene-based materials are potential components used in water treatment on different modes and processes. Ibuprofen and ciprofloxacin are two commonly found pharmaceutical contaminants discharged into water bodies from industrial, domestic and hospital sources. Their concentration levels in water bodies are reported in the range of 1 µg/L to 6.5 mg/L and 0.050-100 µg/L respectively. Their toxic effects pose very high risk to the inhabiting organisms. Their ability to resist biodegradation and capacity to bioaccumulate makes the conventional methods less effective in removal. In the present article, treatment of these compounds via three methods, adsorption, photocatalytic degradation and electro-fenton reactions using graphene-based materials along with the methods adopted for synthesis and treatment are reviewed. The uptakes obtained by graphene-derived adsorbents are presented along with the optimal operating conditions. Studies reported complete removal of ibuprofen from wastewater was achieved at 7 pH for 60 min using graphene membrane as adsorbent and uptake of 99% of ciprofloxacin was exhibited for graphene nanoplates/boron nitrate aerogel at a pH of 7 and 60 min. The reduced graphene oxide surface exhibits higher affinity to light adsorption which leads to the formation of photo generated electrons. The future perspectives for improved applications of graphene-based materials and the research gap currently existing are highlighted.


Asunto(s)
Contaminantes Ambientales , Grafito , Contaminantes Químicos del Agua , Adsorción , Ciprofloxacina/química , Grafito/química , Ibuprofeno , Preparaciones Farmacéuticas , Contaminantes Químicos del Agua/química
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